Student Store Cupboard

"The ingredients and method - are on the blackboard - you will find everything you need — in the store cupboard —
you have an hour and a half ... start."
-- Severus Snape (OP12)

A cupboard in the Potions classroom filled with ingredients for use in class.

The first time the student store cupboard opened was in Snape's class during fifth year as the Potions class was attempting to make the Draught of Peace, often brewed as part of the O.W.L. exam (OP12). So the ingredients powdered moonstone and syrup of hellebore must be inside the cupboard.

It contained "unicorn horns and tangles of dried herbs," and at the very back, Harry found a box of Bezoars to use as an antidote, which won him 10 points to Gryffindor for "sheer cheek" (HBP18)

Slughorn kept the student store cupboard open while the class made Draught of the Living Death, so the ingredients asphodel and wormwood (PS8), valerian roots and sopophorous bean (HBP9) must be kept in the student store cupboard. Following the instructions of the Half-Blood Prince in his potions book, Harry made his Draught of Living Death perfectly and won a vial of Felix Felicis, or "Liquid Luck" (HBP9).

Snape also had a "private store cupboard" in his office in which he kept more exotic ingredients away from students who might made "illicit mixtures" (GF25). In second year, Harry created a diversion by blowing up Goyle's cauldron with a firework while Hermione sneaked into Snape's office and stole boomslang skin and bicorn horn for the Polyjuice Potion (CS11). In fourth year, Snape accused Harry of stealing Polyjuice ingredients again, but that time it was actually the Fake Moody/Barty Crouch Jr (GF27). That same year, Dobby the house-elf stole Snape's gillyweed (at the suggestion of the Fake Moody) and gave it to Harry to use during the Second Task of the Tri-Wizard Tournament. By then, Snape was so suspicious of Harry he threatened to put Veritaserum in his pumpkin juice (GF26, GF27).